JPH10134357A - optical disk - Google Patents

Abstract

(57) [Problem] To provide an optical disk which is a DVD-R that can be accessed at high speed and can perform high-density rewritable recording. SOLUTION: An optical disk A.1 of a zone CAV system or a zone CLV system formed by dividing a groove 1 into zones in a radial direction. A ′, the groove 1 is wobbled in the groove width direction a at a single wobble frequency, and the groove widths 1a to 1c,... It is constant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a rewritable or write-once (WO, additional recording) optical disk which can be accessed at high speed.

[0002]

2. Description of the Related Art At present, a DVD (Digital Video Disc) -R having a larger capacity than a so-called "CD (Compact Disc) -R (Recordable)" is being commercialized. This DVD-R has 3.9G per side
Byte or WO media with a storage capacity of 4.7 GBytes, like a read-only DVD,
A CLV (Constant Linear Velocity) recording method is adopted. The specification of the DVD-R may be a double-sided disk in which a single disk having the same thickness of 0.6 mm as a read-only DVD is bonded, or a single-sided disk in which one is a dummy plate. The track pitch is 0.8 μm and the shortest pit length is 0.44 μm. On the other hand, the wavelength of a recording laser beam for recording information by irradiating spiral continuous guide grooves (grooves, empty grooves) forming a recording area of a DVD-R, and
The wavelength of the reproducing laser beam for irradiating the continuous guide groove and reproducing the information recorded therein is 635 nm.
６650 nm.

By the way, the CLV system is shown in FIG.
As shown in (D) to (D), this is a recording method in which the linear velocity is constant from the inner circumference to the outer circumference of the disk (shown in FIG. 2B), and is therefore inversely proportional to the recording / reproducing position in the groove. As described above, it is necessary to temporarily reduce the rotation speed of the disk on the outer peripheral side from the inner peripheral side (illustrated in FIG. 1A). In addition, it is necessary that the transfer rate and the linear density are constant from the inner circumference to the outer circumference of the disk (shown in FIGS. 3C and 3D).

In the DVD-R, a groove 1 is formed with a minute displacement (wobble) in the radial direction at a constant frequency so as to obtain a constant linear density from the inner circumference to the outer circumference of the disk. By controlling the number of revolutions of the disc so that the reproduced wobble frequency (single carrier frequency) is always constant, CLV recording / reproduction is enabled. This wobbling is performed to prevent disc copying.

[0005] As described above, the wobble state in the DVD-R is such that the value of one cycle of the wobble formed in each groove 1 gradually increases in proportion to going from the inner circumference to the outer circumference of the disk. As a result, as shown in FIG. 17, each groove 1 randomly wobbles in the radial direction, so that the groove widths 1a to 1c,.
Are not constant, and the land widths 2a to 2d,.

[0006]

The above-mentioned DVD-R has the following problems. That is, DVD of CLV system
When -R is used, it is necessary to finely adjust the rotational speed of the disk in accordance with the data recording position in the radial direction to constantly control the linear velocity and the wobble frequency.
For this reason, the DVD-R of the CLV system can perform high-density recording at a constant transfer rate and linear density at the time of data recording, but at the time of reproduction (especially at the time of seeking) at the position where the seek was performed. There is a problem that it takes time to reach a predetermined number of rotations of the disk which is uniquely determined correspondingly, making high-speed access difficult.

Therefore, the present invention has been made to solve the above problems by focusing on the above-mentioned problems, and provides the following optical discs (1) to (4).

(1) As shown in FIG. 1, a data recording area R extending from the inner circumference to the outer circumference of a disk is divided into a large number of zones z concentrically, and excluding each zone boundary sb, the groove width direction The object of the present invention is to provide a WO or rewritable optical disk having a structure in which the wobble frequency of a wobble that slightly displaces to a is constant.

(2) In addition, an optical disk having such a structure is used for an optical disk of ZCAV (Zoned Constant Angular Velocity, zone CAV) type (having the characteristics shown in FIG. 15) or a ZCLV (Zoned Constant Linear Velocity).
The optical disk is provided as an optical disk (having the characteristics shown in FIG. 16) of the elocity (zone CLV) system.

(3) Further, the present invention does not divide the data recording area R into a large number of zones z concentrically, but keeps the groove widths 1a to 1c,. The present invention provides a type optical disk.

(4) Further, the present invention provides an optical disk having such a structure as a CLV optical disk or a CAV optical disk.

[0012]

In order to solve the above-mentioned problems, the present invention provides an optical disk having the following constitutions (1) and (2).

(1) As shown in FIGS. 1 to 3, information (data) is recorded or recorded information (data)
Has a spiral groove 1 for reproducing the optical disk A. The optical disk A. (ZCAV or ZCLV system) is formed by dividing the groove 1 into zones in the radial direction. In A ', the groove 1 is displaced (wobble) in the groove width direction a according to a specific displacement frequency (single carrier frequency, single wobble frequency), and the groove widths 1a to 1a are excluded except for the zone boundary sb. The optical disk is characterized in that 1c,... Are substantially constant over the entire circumference of the disk (the phases of the wobbled groove widths 1a to 1c,... In each zone z are the same).

(2) In an optical disc having a spiral groove 1 for recording information (data) or reproducing the recorded information (data),
Are displaced (wobbled) in the groove width direction a according to a specific displacement frequency (single carrier frequency, single wobble frequency), and the groove widths 1a to 1c,. R) that is substantially constant over the entire recording area R (groove width 1 wobbled in the recording area R)
a to 1c,... have the same phase).

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an optical disk according to the present invention will be described with reference to FIGS. 1 to 13 and FIGS.
FIG. 1 is a view for explaining the overall structure of the optical disc of the present invention, FIG. 2 is an enlarged view for explaining the structure of the optical disc of the present invention, and FIG. 3 is a view showing a wobbled groove land state in the optical disc of the present invention. FIG. 4 is a diagram for explaining a groove land state at a zone boundary of the optical disc of the present invention, and FIG.
FIGS. 6 and 12 are diagrams for explaining various characteristics (disk rotation speed, linear velocity, transfer rate, and linear density) of an AV optical disk. FIGS. 6 and 12 are first and second motor control blocks for driving the optical disk of the present invention, respectively. FIG.
7 and 13 show first and second embodiments of a motor control block for driving an optical disk according to the present invention, respectively.
FIG. 9 is a diagram for explaining various characteristics (disc rotation speed, linear velocity, transfer rate, linear density) of a general ZCLV optical disk, and FIG. 9 is a wobbled groove land state of a general CLV optical disk. FIG. 10 is a diagram for explaining a wobble signal amplitude obtained by reproducing a general CLV optical disk having wobbled groove lands, and FIG.
FIG. 14 is a diagram for explaining the wobble signal amplitude reproduced from the optical disc of the present invention, and FIG. 14 is a diagram for explaining various characteristics (disc rotation speed, linear velocity, transfer rate, linear density) of a general CLV optical disc. FIG. 15 shows ZCAV.
FIG. 16 is a diagram for explaining various characteristics (wobble frequency, disk rotation speed) of the optical disk according to the present invention of the ZCLV type, and FIG. 16 is a diagram for explaining various characteristics (wobble frequency, disk rotation speed) of the optical disk of the present invention of the ZCLV system. FIG.

The optical disk of the present invention is used for DVD-R which is the above-mentioned WO medium, and as shown in FIG. 1, concentrically moves from the inner circumference to the outer circumference in a recording area R having a radius r. A plurality of zones z are sequentially formed (four zones z in the example of FIG. 1), and this recording region R is concentrically divided by each zone z (so-called zone division). Each zone z is further divided in the circumferential direction by a plurality of sectors s. The wobble frequency at which all the grooves 1 in each of the divided zones z are slightly displaced (wobble) in the radial direction is constant.

That is, in the optical disk of the present invention, as shown in FIG. 2, the groove widths 1a to 1c,... Of the groove 1 are the same size (as shown in FIG. 3, the groove width 1a = groove width 1b = groove width 1c). ), And the land widths 2a to 2d,... Of the lands 2 have the same dimensions (as shown in FIG.
(Land width 2a = land width 2b = land width 2c = land width 2d ...). Thus, as shown in FIG. 1, the wobbled groove widths 1a to 1c,... Starting from the start line sc of each zone boundary sb have the same phase in each zone z.

The address indicating the location of the recording data is recorded in advance by forming a pre-pit on the land 2 as shown in FIG. Data is recorded in the groove 1 associated with the land pit 2p to which the address is assigned.

As described above, the addressing structure formed by the wobbled groove 1 and the land pit 2p has, for example, a track pitch (groove width + land width) of the groove 1 of 0.8 μm and groove widths 1a to 1a.
When c,... is 0.4 μm, the displacement of the groove 1 due to wobbling is ± 40 nm, the wobble frequency is a single frequency, and the length of the wobble shape per cycle is 50 μm.
The front and rear portions are formed so as to be substantially constant over the entire circumference of the disk.

The start line sc of the zone boundary sb is
As shown in FIG. 4, each time the optical disc A makes one rotation,
In order to make the optical disk A appear once, the groove width and the land width are changed only in a specific area portion each time the optical disk A makes one rotation (in FIG. The start position 2AB and the end position 2AA of the land 2 corresponding to one rotation are shown).

That is, the groove width 1aa of the groove 1 = the groove width 1ab = the groove width 1ac = the groove width 1ad.
= Groove width 1ae, but land width 2ab ≠ land width 2ac. The groove width 1ba = groove width 1bb = groove width 1bc = groove width 1bd = groove width 1be, but the land width 2bc ≠ the width 2bd.

Incidentally, the optical disk of the present invention has a ZCAV
Any of the system and the ZCLV system can be configured. Hereinafter, [the optical disk A of the present invention of the ZCAV system], [the general optical disk of the ZCAV system], [ZCV]
Optical disc A ′ of the present invention of LV system], [General ZC
LV optical disk].

[Optical disc A of the present invention of ZCAV system]
The optical disk A of the present invention of the ZCAV system is shown in FIGS.
As shown in (A) and (B), the recording area R from the inner circumference to the outer circumference of the disk is divided concentrically into a number of zones z. Spiral groove 1 in each zone z
Are displaced (wobbled) in the groove width direction a by a single wobble frequency determined for each zone z. As a result, the groove widths 1a to 1c,... Are constant over the entire circumference. The optical disk A is constantly driven to rotate at a constant disk rotation speed, and accordingly, a single wobble frequency defined for each zone z is stepped in proportion to the radial direction of the disk. It is supposed to increase.

[General ZCAV System Optical Disk] A general ZCAV system optical disk corresponding to the aforementioned [ZCAV system optical disk A of the present invention] is shown in FIG.
This will be described with reference to (A) to (D). A general ZCAV type optical disc does not have the same groove width in each zone z, whereas a ZCAV type optical disc A has the same groove width in each zone z over the entire circumference. This is the difference.

This general ZCAV type optical disk is always driven to rotate at a constant disk rotation speed (shown in FIG. 3A). As a result, the linear velocity gradually increases from the inner circumference to the outer circumference of the disk. It increases (illustrated in FIG. 6B). Further, the transfer rate is gradually increased in a stepwise manner in proportion to the position of the zone z in the radial direction (illustrated in FIG. 3C).
Although it changes minutely in proportion to the position in the radial direction, the minute change amount is constant in all the zones z (shown in FIG. 3D).

[Optical disk A 'of ZCLV system]
FIG.
As shown in (A) and (B), the recording area R from the inner circumference to the outer circumference of the disk is divided concentrically into a number of zones z. Spiral groove 1 in each zone z
Are displaced (wobbled) in the groove width direction a by a single wobble frequency determined for each zone z. As a result, the groove widths 1a to 1c,... Are constant over the entire circumference. The optical disc A 'is rotationally driven so as to always obtain a constant wobble frequency. For this reason, the rotational speed is sequentially reduced in a stepwise manner in inverse proportion to the radial zone z position. is there.

[General Optical Disk of ZCLV System] With respect to the general optical disk of the ZCLV system for the {optical disk A ′ of the ZCLV system, FIG.
This will be described with reference to FIG. While the general ZCLV optical disk has the same groove width in each zone z, the ZCLV optical disk A ′ has the same groove width in each zone z over the entire circumference.
This is the only difference between the two.

In this general ZCLV optical disk, in order to always obtain a constant linear velocity, the number of disk rotations is gradually reduced stepwise in inverse proportion to the zone z position in the radial direction (FIG. As a result, although the linear velocity slightly changes in proportion to the position in the radial direction in each zone z, the small change amount becomes constant in all the zones z (see FIG. 8B). (Illustration). Further, the transfer rate is always constant irrespective of the position of each zone z (shown in FIG. 4C). Further, although the linear density changes minutely in inverse proportion to the radial position in each zone z, The small change amount is constant in all the zones z (illustrated in FIG. 3D).

The rotation of the optical disk A of the present invention of the ZCAV system and the optical disk A 'of the present invention of the ZCLV system will be described in the following [Z
Rotational drive of CAV optical disk A), [Data recording on ZCAV optical disk A], [Data reproduction from ZCAV optical disk A], [Rotary drive of ZCLV optical disk A '], [ZCLV optical disk A'] Data recording on optical disc A '] and [Data reproduction from optical disc A' of ZCLV method] will be described in this order.

[Rotary drive of ZCAV type optical disc A] As shown in FIG. 6, the motor control block 10 for rotatingly driving the ZCAV type optical disc A has a 1 / N
Frequency dividing circuit 10a, servo circuit 10b, motor 10c, frequency generating circuit (FG) 10d, band-pass filter (B
PF) 10e.

The motor control block 10 having the above configuration
Operates as follows. That is, as shown in FIG. 6, a clock Xtal output from an oscillation circuit (not shown) is frequency-divided into 1 / N by a 1 / N frequency dividing circuit 10a, and then one input signal to a servo circuit 10b as a spindle reference signal. Is output as This spindle reference signal is a rotation reference signal for constantly obtaining a constant disk rotation speed regardless of the radial zone z position when a recording head (pickup) (not shown) scans (reproduces) on the optical disk A. . The frequency generating circuit 10d generates a frequency signal corresponding to the rotation of the spindle of the motor 10c, and outputs this frequency signal to the servo circuit 10b as the other input signal. The servo circuit 10b compares the deviation (difference) of the frequency signal with respect to the spindle reference signal, and outputs a motor drive signal (drive current) to the motor 10c so that the difference becomes zero.

In this way, the motor control block 10 can drive the optical disc A to be rotated so that the number of revolutions of the optical disc A placed on the turntable (not shown) is always constant.

[Data Recording on Optical Disk A of ZCAV System] At the time of data recording, a laser light source of a recording head (not shown) irradiates a groove 1 of the optical disk A and lands 2 and 2 at both ends of the groove 1. The data is wobbled and recorded in the groove 1 by the recording laser beam to be recorded. At the same time, the return light of the recording laser light (reflected light from the optical disk A) is incident on a four-divided detector (not shown). The quadrant detector detects a recording position state obtained by dividing the reflected light into four, and outputs a Push-Pull signal, which is a tracking error detection signal, to the bandpass filter 10e. The Push-Pull signal includes a fluctuation component due to the wobbling described above, and the fluctuation component has a single wobble frequency component.

The Push-Pull signal is output to a recording system (not shown) as a recording reference clock after a signal component of an unnecessary band other than the wobble frequency component is removed by the band-pass filter 10e. In the recording system, it is determined whether or not the reference clock corresponds to the normal wobbling signal amplitude, and the recording operation of the recording head is controlled based on the result of the determination. On the other hand, as described in [Rotation driving of the optical disk A of the ZCAV system], the optical disk A is rotationally driven so that the rotation speed of the optical disk A mounted on the turntable is always constant. Needless to say. Therefore, stable ZCAV recording is always possible.

[Data Reproduction from Optical Disk A of ZCAV System] During data reproduction, a laser light source of a pickup (not shown) straddles the data recorded groove 1 of the optical disk A and the lands 2 and 2 at both ends of the groove 1. The data recorded by wobbling on the groove 1 is reproduced by the reproducing laser light irradiated. At the same time, the return light of the reproduction laser light (reflected light from the optical disk A) enters a four-divided detector (not shown). The four-segment detector detects a reproduction position state obtained by dividing the reflected light into four parts, and push-pulls a tracking error detection signal, Push-Pu.
11 is output to the bandpass filter 10e. The Push-Pull signal includes a fluctuation component due to the wobbling described above, and the fluctuation component has a single wobble frequency component.

The Push-Pull signal is output to a reproduction system (not shown) as a reproduction reference clock after a signal component of an unnecessary band other than the wobble frequency component is removed by the band-pass filter 10e. In the reproducing system, it is determined whether or not this reference clock has a normal wobbling signal amplitude, and the reproducing operation of the pickup is controlled based on the result of the determination. On the other hand, as described in [Rotation driving of the optical disk A of the ZCAV system], the optical disk A is rotationally driven so that the rotation speed of the optical disk A mounted on the turntable is always constant. Needless to say. Therefore, always stable ZCAV reproduction can be performed.

[Rotary drive of the ZCLV type optical disk A '] The motor control block 11 for rotatingly driving the ZCLV type optical disk A', as shown in FIG.
N frequency dividing circuit 11a, servo circuit 11b, motor 11c,
It is composed of a band pass filter (BPF) 11d and a 1 / N 'frequency dividing circuit 11e.

The motor control block 11 having the above configuration
Operates as follows. That is, as shown in FIG. 7, a clock Xtal output from an oscillation circuit (not shown) is frequency-divided into 1 / N by a 1 / N frequency dividing circuit 11a, and one input signal to a servo circuit 11b is used as a spindle reference signal. Is output as This spindle reference signal is recorded (reproduced) on an optical disk A 'by a recording head (pickup) (not shown).
This is a rotation reference signal for obtaining a disk rotation number that gradually decreases in a stepwise manner in inverse proportion to a radial zone z position at the time of scanning. As will be described later, a recording / reproducing reference clock obtained through a Push-Pull signal band-pass filter 11d and a 1 / N 'frequency dividing circuit 11e is used as the other input signal input to the servo circuit 11b. The servo circuit 11b compares the deviation (difference) of the reference clock with respect to the spindle reference signal, and outputs a motor drive signal (drive current) to the motor 10c such that the difference becomes zero.

In this way, the motor control block 11 sequentially changes the rotation speed of the optical disk A 'placed on the turntable (not shown) in a stepwise manner in inverse proportion to the radial zone z position at the time of recording (reproducing) scanning. The optical disc A can be driven to rotate so as to reduce the number.

[Data Recording on Optical Disk A 'of ZCLV System] At the time of data recording, a groove 1 of the optical disk A' and a groove 1 of the optical disk A 'are transmitted from a laser light source of a recording head (not shown).
The data is recorded while being wobbled in the groove 1 by the recording laser beam applied over the lands 2 and 2 at both ends of the groove 1. At the same time, the return light of the recording laser light (reflected light from the optical disk A ') enters a four-divided detector (not shown). The quadrant detector detects a recording position state obtained by dividing the reflected light into four, and outputs a Push-Pull signal as a tracking error detection signal to the bandpass filter 11d. The Push-Pull signal includes a fluctuation component due to the wobbling described above, and the fluctuation component has a single wobble frequency component.

After the Push-Pull signal is subjected to removal of unnecessary band signal components other than the wobble frequency component by the band-pass filter 11d, the Push-Pull signal becomes 1 as a recording reference clock.
/ N 'frequency dividing circuit 11e and a recording system (not shown). In the recording system, it is determined whether or not the reference clock corresponds to the normal wobbling signal amplitude, and the recording operation of the recording head is controlled based on the result of the determination.

The recording reference clock output to the 1 / N 'frequency dividing circuit 11e is frequency-divided by 1 / N' and then output to the servo circuit 11b as the other input signal. The servo circuit 11b compares the deviation (difference) of the wobble signal divided by 1 / N 'with respect to the spindle reference signal, and outputs a motor drive signal to the motor 11c so that the difference becomes zero.

On the other hand, as described in [Rotation driving of the optical disk A 'of the ZCLV system], the zone z position in the radial direction when the number of rotations of the optical disk A' mounted on the turntable is recorded and scanned. It is needless to say that the optical disk A 'is rotationally driven so as to gradually decrease in a stepwise manner in inverse proportion to. Therefore, stable ZCLV recording is always possible.

[Reproduction of Data from Optical Disk A 'of ZCLV System] During data reproduction, a laser light source of a pickup (not shown) straddles the data recorded groove 1 of the optical disk A' and the lands 2 and 2 at both ends of the groove 1. The data recorded by wobbling on the groove 1 is reproduced by the reproducing laser beam which is subsequently irradiated. At the same time, the return light of the reproduction laser light (reflected light from the optical disk A ') enters a four-divided detector (not shown). The four-segment detector detects a reproduction position state obtained by dividing the reflected light into four parts, and determines a Push error which is a tracking error detection signal.
-Output the Pull signal to the band pass filter 11d. The Push-Pull signal includes a fluctuation component due to the wobbling described above, and the fluctuation component has a single wobble frequency component.

The Push-Pull signal is output to a reproduction system (not shown) as a reproduction reference clock after signal components in unnecessary bands other than the wobble frequency component are removed by the band-pass filter 11d. In the reproducing system, it is determined whether or not this reference clock has a normal wobbling signal amplitude, and the reproducing operation of the pickup is controlled based on the result of the determination.

The reproduction reference clock output to the 1 / N 'frequency dividing circuit 11e is frequency-divided by 1 / N' and then output to the servo circuit 11b as the other input signal. The servo circuit 11b compares the deviation (difference) of the wobble signal divided by 1 / N 'with respect to the spindle reference signal, and outputs a motor drive signal to the motor 11c so that the difference becomes zero.

On the other hand, as described in [Rotation driving of the optical disk A 'of the ZCLV system], the zone z position in the radial direction at the time of reproducing and scanning the rotational speed of the optical disk A' mounted on the turntable. It is needless to say that the optical disk A 'is rotationally driven so as to gradually decrease in a stepwise manner in inverse proportion to. Therefore, stable ZCLV reproduction is always possible.

By the way, in reproducing a general CLV type optical disk having the various characteristics (disk rotation speed, linear velocity, transfer rate, and linear density) shown in FIG. The level of the wobble signal obtained from the recorded groove 1 and the return light (reflected light) of the reproduction laser light applied across the lands 2 and 2 at both ends of the groove 1 varies as follows. In a reproduction system using such a wobble signal,
It has been essential to perform waveform shaping to remove a variation in level and obtain a wobble signal of a constant level.

That is, as shown in FIG.
ウ ォ In the wobble signal waveform obtained based on the return light of the reproduction laser light that scans the position AA having a width of 2 cb, the phases of the wobbles do not match in the groove width direction a. For this reason, the amplitude of the wobble signal waveform thus obtained is a level indicated by a broken line, as in the wobble signal amplitude shown on the left side in FIG. 10, and is relatively low.

On the other hand, as shown in FIG. 9, a rarely existing wobble signal waveform obtained based on the return light of the reproduction laser beam scanning the position AB having the land width 2da = width 2db has a wobble signal waveform. Are matched in the groove width direction a. Therefore, the amplitude of the wobble signal waveform thus obtained is higher than the level indicated by the broken line, like the wobble signal amplitude shown on the right side in FIG.
As described above, the level of the wobble signal reproduced varies depending on the scanning position when reproducing a general CLV optical disk.

In reproducing the optical disk A of the present invention by the ZCAV system or the optical disk A 'of the present invention by the ZCLV system, as shown in FIGS. 3 and 4, the zone boundary sb (the land 2 Except for the start position 2AB and the end position 2AA), the land width is formed constant so that the phases of the wobbles coincide in the radial direction over the entire circumference of the disk. Needless to say, the level of the wobble signal obtained based on the return light of the reproduction laser light irradiated across the lands 2 and 2 at both ends is always constant.

As a result, in a reproducing system using such a wobble signal, it is possible to use a wobble signal without performing waveform shaping to remove a variation in level to obtain a constant level wobble signal.

That is, the lands 2 and 2 at both ends of the groove 1 have the same land width except for the zone boundary sb.
As in the case of the wobble signal amplitude shown in FIG. 11, a constant level wobble signal can always be obtained. Thus, ZC
Optical disc A or ZCLV of the present invention by AV system
When reproducing the optical disc A 'of the present invention by the method, a wobble signal having a constant amplitude and high reliability can be obtained.

Now, the above-described ZCAV system or ZC
Each of the optical discs A and A 'of the present invention of the LV system has
The optical disk A1 or A1 'of the present invention of the CAV system or the CLV system described below is a disk having no zone boundary sb. A,
Similarly to A ′, the optical disk has all the groove widths 1a to 1c,... (All the land widths 2a to 2d,. The structure of the optical disks A1 and A1 'of the present invention of the CAV system or the CLV system is different from the above-mentioned optical disks A and A' of the ZCAV system or the ZCLV system only in that the optical disk does not have the zone boundary sb. Other structures are the same.

That is, each of the optical disks A1 and A1 'of the present invention of the CAV system or the CLV system has the W
O-media used for DVD-R,
As shown in FIG. 1, in a recording area R having a radius r, a plurality of zones z are not sequentially formed concentrically from the inner circumference to the outer circumference, but are formed in a circumferential direction or a radial direction by a plurality of sectors s. This is a disk with a divided structure. The wobble frequency at which all the grooves 1 in each sector s are slightly displaced (wobble) in the radial direction is constant.

As shown in FIG. 2, the optical discs A1 and A1 'have groove widths 1a to 1c,.
, The groove width 1a = the groove width 1b = the groove width 1c...
.. Have the same dimensions (land width 2a as shown in FIG. 3).
= Land width 2b = land width 2c = land width 2d ...). Thus, as shown in FIG. 1, the wobble shape has the same phase in the radial direction of each sector s.

The address indicating the location of the recording data is recorded in advance by forming a prepit on the land 2 as shown in FIG. Data is recorded in the groove 1 associated with the land pit 2p to which the address is assigned.

As described above, in the addressing structure formed by the wobbled groove 1 and the land pit 2p, for example, the track pitch of the groove 1 is set to 0.
When the groove width is 8 μm and the groove widths 1 a to 1 c are 0.4 μm, the displacement of the groove 1 due to wobbling is ± 40 n.
m, the wobble frequency is a single frequency, the length of the wobble shape per cycle is about 50 μm, and it is formed so as to be substantially constant over the entire circumference of the disk.

The rotational driving of the optical disk A1 of the present invention of the CAV method and the optical disk A1 'of the present invention of the CLV method will be described below. Data recording on optical disc A1], [Reproduction of data from CAV optical disc A1], [CLV optical disc A]
1], [recording data on the CLV optical disc A1 '], and [reproducing data from the CLV optical disc A1'].

[Rotational Drive of CAV System Optical Disk A1] As shown in FIG. 12, a motor control block 10A for rotationally driving the CAV system optical disk A1 includes:
/ N frequency dividing circuit 10a, servo circuit (rotary servo) 10
b, motor 10c, frequency generating circuit (FG) 10d, band-pass filter (BPF) 10e, 1 / M frequency dividing circuit 1
0Aa, and a multiplication circuit (the number of X sectors) 10Ab. The same components as those described above are denoted by the same reference numerals.

The motor control block 10A having the above configuration
Operates as follows. That is, as shown in FIG. 12, the clock Xtal output from the oscillation circuit (not shown) is 1 / N
After being divided into 1 / N by the frequency dividing circuit 10a, it is output as one input signal to the servo circuit 10b as a spindle reference signal. This spindle reference signal is a rotation reference signal for constantly obtaining a constant disk rotation speed irrespective of the position at which the recording head (pickup) (not shown) performs recording (reproduction) scanning on the optical disk A1. Frequency generation circuit 10
d generates a frequency signal corresponding to the rotation of the spindle of the motor 10c, and outputs this frequency signal to the servo circuit 10b as the other input signal. The servo circuit 10b compares the deviation (difference) of the frequency signal with respect to the spindle reference signal, and outputs a motor drive signal (drive current) to the motor 10c so that the difference becomes zero.

Thus, the motor control block 10 can rotationally drive the optical disk A1 mounted on the turntable (not shown) so that the rotational speed of the optical disk A1 is always constant.

[Data Recording on CAV Optical Disc A1] At the time of data recording, a laser light source of a recording head (not shown) irradiates a groove 1 of the optical disc A1 and lands 2 and 2 at both ends of the groove 1. The data is wobbled and recorded in the groove 1 by the recording laser beam to be recorded. At the same time, the return light of the recording laser light (reflected light from the optical disk A1) is incident on a four-divided detector (not shown). The quadrant detector detects a recording position state obtained by dividing the reflected light into four, and outputs a Push-Pull signal, which is a tracking error detection signal, to the bandpass filter 10e. The Push-Pull signal includes a fluctuation component due to the wobbling described above.
This fluctuation component has a single wobble frequency component.

The Push-Pull signal is supplied to a 1 / M frequency dividing circuit 10Aa after a signal component of an unnecessary band other than the wobble frequency component is removed by a band-pass filter 10e, where the signal is divided by 1 / M. Is supplied to the multiplication circuit 10Ab, where it is multiplied according to the sector s during the printing scan, and then output to a printing system (not shown) as a printing reference clock. In the recording system, it is determined whether or not the reference clock corresponds to the normal wobbling signal amplitude, and the recording operation of the recording head is controlled based on the result of the determination. On the other hand, as described in [Rotation driving of the CAV type optical disk A1], the rotation speed of the optical disk A1 placed on the turntable is always kept constant.
It goes without saying that the optical disc A1 is driven to rotate. Therefore, always stable CAV recording can be performed.

[Data Reproduction from Optical Disk A1 of CAV Method] During data reproduction, a laser light source of a pickup (not shown) straddles the data recorded groove 1 of the optical disk A1 and the lands 2 and 2 at both ends of the groove 1. The data recorded by wobbling on the groove 1 is reproduced by the reproducing laser light irradiated. At the same time,
Return light of reproduction laser light (reflected light from optical disk A1)
Enters a four-divided detector (not shown). The quadrant detector detects a reproduction position state obtained by dividing the reflected light into four parts, and determines a Push-P signal which is a tracking error detection signal.
The ul signal is output to the band pass filter 10e. The Push-Pull signal includes a fluctuation component due to the wobbling described above, and the fluctuation component has a single wobble frequency component.

The Push-Pull signal is supplied to a 1 / M frequency dividing circuit 10Aa after a signal component of an unnecessary band other than the wobble frequency component is removed by a band-pass filter 10e, and is then divided by 1 / M. After being supplied to the multiplication circuit 10Ab and multiplying the signal there, the wobble frequency signal corresponding to each sector s of the optical disc A1 is output to a reproduction system (not shown) as a reproduction reference clock. In the reproducing system, it is determined whether or not this reference clock has a normal wobbling signal amplitude, and the reproducing operation of the pickup is controlled based on the result of the determination. On the other hand, as described in [Rotation driving of CAV type optical disk A1], the optical disk A1 is rotationally driven so that the rotational speed of the optical disk A1 mounted on the turntable is always constant. Needless to say. Therefore, always stable CAV reproduction can be performed.

[Rotary driving of the CLV type optical disk A1 '] The motor control block 11A for rotationally driving the CLV type optical disk A1' has a structure as shown in FIG.
1 / N frequency dividing circuit 11a, servo circuit (rotary servo) 11
b, motor 11c, band pass filter (BPF) 10
d, 1 / R divider circuit 11Aa, 1 / M divider circuit 11Ab
Consists of The same components as those described above are denoted by the same reference numerals.

The motor control block 11A having the above configuration
Operates as follows. That is, as shown in FIG. 13, the clock Xtal output from the oscillation circuit (not shown) is 1 / N
After being divided by the dividing circuit 11a to 1 / N, the signal is divided by the 1 / R dividing circuit 11Aa into 1 / R, and output as one input signal to the servo circuit 11b as a spindle reference signal. This spindle reference signal is recorded (reproduced) on the optical disk A1 'by a recording head (pickup) (not shown).
This is a rotation reference signal for obtaining a disk rotation number that sequentially decreases in inverse proportion to a radial position at the time of scanning. The 1 / R frequency dividing circuit 11Aa is supplied with a recording / reproducing position information signal for each sector, whereby the input signal divided by 1 / N at a dividing ratio corresponding to the recording / reproducing position is further divided by 1 / R. Go around. As described later, as the other input signal to be input to the servo circuit 11b, a recording / reproducing reference clock obtained by the Push-Pull signal obtained through the band-pass filter 11d and the 1 / M frequency dividing circuit 11Ab is used. The servo circuit 11b compares the deviation (difference) of the reference clock with respect to the spindle reference signal, and outputs a motor drive signal (drive current) to the motor 11c so that the difference becomes zero.

Thus, the motor control block 11A sequentially decreases the rotation speed of the optical disc A1 'placed on the turntable (not shown) in inverse proportion to the radial position at the time of recording (reproducing) scanning. This optical disk A1 '
Can be driven to rotate.

[Data Recording on CLV Optical Disc A1 '] At the time of data recording, a laser light source of a recording head (not shown) straddles the groove 1 of the optical disc A1' and the lands 2 and 2 at both ends of the groove 1. The data is wobbled and recorded on the groove 1 by the recording laser light irradiated. At the same time, the return light of the recording laser light (reflected light from the optical disk A1 ') is incident on a four-divided detector (not shown). The quadrant detector detects a recording position state obtained by dividing the reflected light into four, and outputs a Push-Pull signal as a tracking error detection signal to the bandpass filter 11d. This Push-Pul
The 1 signal includes the above-mentioned wobbling fluctuation component, and this fluctuation component has a single wobble frequency component.

After this Push-Pull signal is subjected to removal of signal components in unnecessary bands other than the wobble frequency component by the band-pass filter 11d, the signal becomes 1 as a recording reference clock.
/ M frequency dividing circuit 11Ab and a recording system (not shown). In the recording system, it is determined whether or not the reference clock corresponds to the normal wobbling signal amplitude, and the recording operation of the recording head is controlled based on the result of the determination.

The recording reference clock output to the 1 / M frequency dividing circuit 11Ab is frequency-divided by 1 / M and then output to the servo circuit 11b as the other input signal. The servo circuit 11b compares the deviation (difference) of the wobble signal divided by 1 / M with respect to the spindle reference signal, and outputs a motor drive signal to the motor 11c so that the difference becomes zero.

On the other hand, as described in the above [Rotation driving of the CLV type optical disk A1 '], the rotational speed of the optical disk A1' placed on the turntable is inversely proportional to the radial position at the time of recording and scanning. Needless to say, the optical disc A1 'is rotationally driven so as to sequentially decrease. Therefore, stable CLV recording can be performed at all times.

[Data Reproduction from Optical Disk A1 'of CLV Method] At the time of data reproduction, a data recorded groove 1 of the optical disk A1' is supplied from a laser light source of a pickup (not shown).
The data recorded by wobbling on the groove 1 is reproduced by the reproduction laser light applied over the lands 2 and 2 at both ends of the groove 1. At the same time, the return light of the reproduction laser light (reflected light from the optical disk A1 ') is incident on a 4-part detector (not shown). This 4
The split detector detects a reproduction position state obtained by dividing the reflected light into four parts, and outputs a Pus which is a tracking error detection signal.
The h-Pull signal is output to the band pass filter 11d. The Push-Pull signal includes a fluctuation component due to the wobbling described above, and the fluctuation component has a single wobble frequency component.

After the Push-Pull signal is removed from the unnecessary band signal components other than the wobble frequency component by the band-pass filter 11d, the Push-Pull signal is used as a reference clock for reproduction.
The signal is output to the / M frequency dividing circuit 11Ab, where it is frequency-divided by 1 / M, and then output to a reproducing system (not shown) as a reproducing reference clock. In the reproducing system, it is determined whether or not this reference clock has a normal wobbling signal amplitude, and the reproducing operation of the pickup is controlled based on the result of the determination.

The reproduction reference clock output to the 1 / M frequency dividing circuit 11e is frequency-divided by 1 / N 'and then output to the servo circuit 11b as the other input signal. The servo circuit 11b compares the deviation (difference) of the wobble signal divided by 1 / N 'with respect to the spindle reference signal, and outputs a motor drive signal to the motor 11c so that the difference becomes zero.

On the other hand, as described in the above [Rotation driving of the CLV type optical disk A1 '], the rotational speed of the optical disk A1' placed on the turntable is inversely proportional to the radial position at the time of reproduction scanning. Needless to say, the optical disk A 'is driven to rotate so as to sequentially decrease. Therefore, always stable CLV reproduction can be performed.

[0078]

According to the optical disk of the present invention, data is continuously recorded or reproduced without being divided in the recording area, so that it has good compatibility with, for example, a read-only DVD disk. Further, both the ZCAV system and the ZCLV system can be used, which is most suitable for a rewritable optical disk.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining the overall structure of an optical disc according to the present invention.

FIG. 2 is an enlarged view for explaining the structure of the optical disc of the present invention.

FIG. 3 is a diagram for explaining a wobbled groove land state in the optical disc of the present invention.

FIG. 4 is a diagram for explaining a groove land state at a zone boundary of the optical disc of the present invention.

FIG. 5 shows various characteristics (disc rotation speed, linear velocity, transfer rate, linear density) of a general ZCAV optical disk.
FIG. It is.

FIG. 6 is a diagram showing a first embodiment of a motor control block for driving the optical disk of the present invention of the ZCAV system.

FIG. 7 is a diagram showing a first embodiment of a motor control block for driving the optical disk of the present invention of the ZCLV system.

FIG. 8 shows various characteristics (disc rotation speed, linear velocity, transfer rate, linear density) of a general ZCLV optical disk.
FIG.

FIG. 9 is a diagram for explaining a wobbled groove land state in a general CLV optical disk.

FIG. 10 is a diagram for explaining a wobble signal amplitude obtained by reproducing a general CLV optical disk having wobbled groove lands.

FIG. 11 is a diagram for explaining a wobble signal amplitude obtained by reproducing the optical disc of the present invention.

FIG. 12 is a diagram showing a second embodiment of a motor control block for driving the optical disk of the present invention of the ZCAV system.

FIG. 13 is a diagram showing a second embodiment of the motor control block for driving the optical disk of the present invention of the ZCLV system.

FIG. 14 shows various characteristics (disc rotation speed, linear velocity, transfer rate, and linear density) of a general CLV optical disk.
FIG.

FIG. 15 is a diagram for explaining various characteristics (wobble frequency, disk rotation speed) of the optical disk of the present invention of the ZCAV system.

FIG. 16 is a diagram for explaining various characteristics (wobble frequency, disk rotation speed) of the optical disk of the present invention of the ZCLV system.

FIG. 17 is an enlarged view for explaining the structure of a conventional optical disc.

[Explanation of symbols]

 1 groove 1a to 1c groove width 2 land 2a to 2d land width 2p land pit a groove width direction A. A1, A ', A'1 optical disk sb zone boundary z zone

Claims (2)

[Claims] 1. An optical disc having a spiral groove for recording information or reproducing the recorded information and dividing the groove into zones in a radial direction, wherein the groove has a specific displacement frequency. An optical disc, wherein the optical disc is displaced in the groove width direction in accordance therewith, and the groove width is substantially constant over the entire circumference except for a zone boundary. 2. An optical disc having a spiral groove for recording information or reproducing the recorded information, wherein the groove is displaced in a groove width direction in accordance with a specific displacement frequency. An optical disc characterized by being substantially constant over the entire circumference.